A wireless communication system includes a plurality of APs and WTRUs. Each AP usually has a fixed location and has a particular coverage area. The WTRUs are capable of moving around the coverage areas of the APs. When a WTRU first enters a coverage area of a particular AP, the WTRU obtains an association with the particular AP. As the WTRU moves out of the coverage area of the AP, the WTRU obtains a new association with another AP and the association with the particular AP is terminated.
The terminology “disassociation” refers to a procedure of informing an associated AP that a WTRU is no longer connected to the associated AP. A WTRU is disassociated from an AP when the WTRU leaves the coverage area of the AP or when the WTRU is turned off for more efficient management of the system. However, under current IEEE 802.11 standards for a wireless local area network (WLAN), a disassociation procedure is optional. Therefore, a manufacturer may or may not incorporate a disassociation procedure into WTRUs used in a WLAN.
An AP makes real-time decisions when admitting new WTRUs by applying a admission control procedure or by applying radio resource management (RRM) algorithms to solve performance problems. The AP monitors the status of the applied resources as well as WTRUs associated with the AP.
However, under the current IEEE 802.11 standards, it is difficult for an AP to monitor the disassociation of WTRUs. Therefore, the AP does not maintain accurate information regarding the status of resources and WTRU association. As a result, the AP is susceptible to making incorrect decisions related to admission control and RRM. This may affect the performance of the WLAN adversely.
A method and system for enabling an AP to manage the association and disassociation of WTRUs is desired.